Tool for slitting cable insulations



BY I

HTTOE 5) 0, m i M M a M 4 a s. m )L mum fifi I m July 11, 1944. s. M. MARTIN TOOL FOR SLLITTING CABLE INSULATION-3 Filed March 27, 1943 Patented July 11, 1944 TOOL FOR SLITTIN G CABLE INSULATIONS Samuel M. Martin, Baltimore, Md., assignor to Western Electric Company, Incorporated, New York, N. Y., a corporation of New York Application March 27, 1943, Serial No. 480,876

17 Claims.

This invention relates to tools for slitting cable insulations of insulated cables and has for its object the provision of new and improved insulation slitting tools.

Often it is desirable to slit the vulcanized rubb'er or other tough plastic insulation of a cable parallel to the longitudinal axis thereof so that the insulation may be easily removed from the cable core.

In accordance with one embodiment of the invention, ther is provided a tool which comprises a frame wherein may be secured any of a number of bushings having openings of various sizes to fit cables of various diameters. The device is provided with arms pivotally mounted on the frame which have cutting members fixed thereto for penetrating the insulation on the cable when the arms are drawn towards each other and for slitting the insulation parallel to the longitudinal axis of the cable when the tool is moved longitudinally relative to the cable.

Other objects and features of the invention will become apparent from the following detailed description, when taken in conjunction with the appended drawing, in which Fig. l is a plan view, partially in section, of an insulation slitting tool embodying the invention;

Fig. 2 is an end view along the line 2-2 as shown in Fig. 1, and

Fig. 3 is a view of an insulated cable showing one of the longitudinal incisions cut in the insulation by the insulation slitting tool.

Referring to Fig. 1 of the drawing, a framelO has an aperture I therein in which a bushing l2 may be inserted and fixedly positioned by a set screw l5. The bushing |2 has a bore l6 therein of approximately the size of an insulated cable 13 whose insulation is to be slit. A plurality of U-shaped sleeves 22-22 are welded or otherwise secured to the frame l0. The sleeves and the members associated therewith are identical and for simplicitys sake only one will be described. The sleeve 22 has a cut out portion 25 therein. An arm 2? is pivotally mounted on a pin 29 in the sleeve 22 and has a handle 30 thereon. The arm 2! has a recessed portion 3| therein to prevent the arm 21 from striking the frame in when it is in the extreme inward position, as shown in full lines in Fig. 1 of the drawing. The arm 21 has an aperture 32 therein in which is adjustably positioned a cutting tool 35 secured against movement relative to the arm 21 by a set screw 39. The cutting tool 35 has a pointed cutting surface 40. The bushing l2 has a plurality of slots 4|-4| therein so that the cutting tools 35-35 may project therethrough and a flange 44 thereon which permits the arms 21-21 to move inwardly only a certain distance and thereby prevents the cutting surface 40 from projecting into a. core 2| of the cable l9, thereby damaging it during the slitting operation.

The openings 25-25 are provided so that when the arms 21-2! are retracted, as shown in dotted lines (Fig. 1), rearward projecting ends 34-34 of the cutting tools 35-35 will not strike the sleeves 22-22 and the cutting tools may be completely withdrawn from the slots 4 |-4| to permit the insertion of the cable l9.

In the operation of this device the arms 21-21 are moved to the dotted line position (Fig. 1) and the cable l9 comprising a layer of rubber composition insulation 20 surrounding the core 2| is inserted in the bore 16 in the bushing l2 to the extent it is desired to have the insulation 20 removed from the core 2|. The arms 27-21 are drawn inwardly as shown in full lines in Fig. 1 so that the cutting surfaces 40-40 project through the insulation 20 on opposite sides of the cable l9, but do not penetrat the core 2|. The cable is then held firmly by any suitable clamping means and the handles 30-30 are grasped by the operator and the tool is moved longitudinally relative to the cable until the tool is completely drawn from the cable. The natural tendency of the pulling on the handles 30-30 is to force the arms 21-21 against the flange 44 and the cutting surfaces 40-40 through the insulation 20 and thereby prevent the cutting surfaces 40-40 from slipping out of the insulation as the tool is drawn from the cable l9. After the completion of this operation, the insulation 20 has two longitudinal slits 33-33 in the opposite sides of the insulation 20. It will be obvious that a slit 33 of any desired length may be produced by the tool hereinabove described.

Obviously, the cutting tools 35-35 may be easily adjusted with respect to the arms 21-21. Bushings l2, having bores of different sizes to correspond to different sizes of insulated cable may be interchanged in the frame I0 and thus the tool may be used to slit the insulation of cables of various sizes.

Various modifications may be made in the apparatus described herein without departing from the spirit and scope of the invention which is limited only by the appended claims. For example, any number of arms 21-21 and cutting tools 35-35 may be provided to cut any number of slits 33-33 which may be desired,

What is claimed is:

1. An insulation cutting tool, comprising a frame having an opening therein, a bushing removably secured in the opening and having a bore therein of approximately the same diameter as an insulated cable which is to be inserted therein, and a pivoted cutting member carried by said frame for movement relative thereto and to an insulated cable inserted through the bore in the bushing and adapted to be grasped for withdrawing the frame from the cable and thereby slit the insulation on the cable.

2. An insulation cutting tool, comprising a frame having an opening therein, a bushing removably secured in the opening and which has a bore therein of approximately the same diameter as an insulated cable which is to be inserted therein, an arm pivotally attached to said frame for movement to and from an insulated cable inserted through the bore in the bushing and adapted to be grasped to draw the frame from the cable, and a cutting blade attached to the arm to slit the insulation of the cable as the frame is drawn from the cable.

3. An insulation cutting tool, comp-rising a frame having an opening therein through which an insulated cable may be inserted, an arm pivotally attached thereto for movement to and from an insulated cable inserted through the opening in the frame and adapted to be grasped to draw the frame from the cable, a cutting blade attached to the arm to slit the insulation of the cable as the frame is drawn from the cable, and means to limit the penetration of the cutting blade into the insulation of the cable.

4. An insulation cutting tool, comprising a frame having an opening therein, a bushing removably secured in the opening and which has a bore therein of approximately the same size as that of an insulated cable which may be inserted therein, an arm pivotally attached to said frame for movement to and from an insulated cable inserted through the bore in the bushing and adapted to be grasped to draw the frame from the cable, a cutting blade attached to the arm to slit the insulation on the cable as the frame is drawn from the cable, and means to limit the penetration of the cutting blade into the insulation of the cable.

5. A tool for slitting insulation on a cable, comprising a frame having an opening therein through which an insulated cable may be inserted, a plurality of arms pivotally attached to the frame and adapted to be grasped to draw the frame parallel to the longitudinal axis of an insulated cable inserted through the opening in the frame, and a cutting member attached to each of the arms and movable therewith to slit the insulation on the cable parallel to the longitudinal axis thereof.

6. A tool for slitting insulation on a cable, comprising a frame having an opening therein through which an insulated cable may be inserted, a plurality of arms pivotally attached to the frame and adapted to be grasped to draw the frame along the longitudinal axis of an insulated cable inserted through the opening to the frame, and a cutting member adjustably attached to the arms and movable therewith to slit the insulation parallel to the longitudinal axis thereof.

'7. A tool for slitting insulation of a cable, comprising a frame having an opening therein, in which a bushing is secured which has a bore of approximately the same diameter as a cable which is to be inserted therethrough, a plurality of arms pivotally attached to the frame and adapted to be grasped to draw the frame parallel to the longitudinal axis of an insulated cable inserted through the bore in the bushing, and a cutting member attached to each of the arms to slit the insulation on the cable parallel to the longitudinal axis thereof.

8. An apparatus for slitting insulation on a cable, comprising a frame, a bushing removably secured in the frame and having an opening therein through which a cable may be inserted and a plurality of longitudinal slots therethrough, a plurality of U-shaped sleeves rigidly attached to the frame and having cut out portions on each, a plurality of L-shaped rods pivotally mounted on the sleeves and adapted to be grasped at their outer ends for moving the frame relative to an insulated cable inserted through the opening in the bushing parallel to longitudinal axis of the insulated cable, and an elongated cuttin member adjustably attached to each of the L- shaped rods and having a cutting portion on one end thereof for slitting the insulation of the cable parallel to the longitudinal axis thereof as the L-shaped rods are moved toward the cable.

9. A tool for slitting insulation on a cable, comprising a frame having an opening therein through which an insulated cable may be inserted, a plurality of arms pivotally attached to the frame and adapted to be grasped to draw the frame longitudinally along an insulated cable inserted through the opening in the frame, a plurality of cutting members attached to the arms to slit the insulation on the cable, and means to prevent the cutting members from penetrating the insulation beyond a predetermined depth.

10. A tool for slitting insulation of a cable, comprising a frame having a opening therein, in which a bushing having a bore of approximately the same diameter as an insulated cable to be inserted therethrough may be secured, a plurality of arms pivotally attached to the frame and adapted to be grasped to draw the frame parallel to the longitudinal axis of an insulated cable inserted through the bore in the bushing, a cutting member attached to each of the arms to slit the insulation on the cable along the longitudinal axis thereof, and means to prevent the cutting members from penetrating the insulation beyond a predetermined depth.

11. A tool for slitting insulation of a cable, comprising a frame having an opening therein, a bushing removably secured in the opening and having a bore therein through which an insulated cable may be inserted, a plurality of arms pivotally attached to the frame for move--- ment with respect to the frame and an insulated cable inserted through the bore in the bushing and adapted to be grasped to draw the frame and the bushing parallel to the longitudinal axis of the cable, a cutting member adjustably attached to each of the arms to slit the insulation on the cable parallel to the longitudinal axis thereof, and means to prevent the cutting members from penetrating the insula tion beyond a predetermined depth.

12. An insulation cutting tool, comprising a frame having an opening therein through which an insulated cable may be inserted, an arm pivotally attached to the frame for movement to and from the opening in the frame to permit a cable to be inserted therethrough and adapted to be grasped to draw the frame from an insulated cable inserted in the opening, and a cutting blade attached to the arm to slit the insulation on the cable as the frame is drawn from the cable.

13. An apparatus for slitting insulation on a cable, comprising a frame, a bushing removably secured in the frame and having an opening therein through which a cable may be inserted and a plurality of slots therethrough, a plurality of U-shaped sleeves rigidly attached to the frame, a plurality of L-shalped rods pivotally mounted on the sleeves and adapted to be grasped at their outer ends for moving the frame along and parallel to longitudinal axis of an insulated cable inserted through the opening in the bushing, an elongated cutting member adjustably attached to each of the L-shaped rods and having a cutting portion on one end thereof designed to pass through one of the slots in the bushing to slit the insulation of the cable parallel to the longitudinal aXiS thereof as the frame is moved along the cable, and means to prevent the cutting members from enetrating the insulation beyond a predetermined depth.

14. An apparatus for slitting insulation on a cable, comprising a frame, a bushing removably secured in the frame and having an opening therein through which a cable may be inserted and a plurality of slots therethrough, a plurality of U-sha-ped sleeves rigidly attached to the frame,

a plurality of L-shaped rods having their inner ends .pivotally mounted on the sleeves and adapted to be grasped at their outer ends for moving the arms toward the opening in the bushing and for advancing the frame along and parallel to longitudinal axis of an insulated cable inserted through the opening in the bushing, an elongated cutting member adjustably attached to each of the L-shaped rods at points intermediate the ends of the rods and having a cutting portion on one end thereof designed to pass through one of the slots in the bushing to penetrate the insulation of the cable as the L-shaped rods are moved toward the cable and to slit the insulation arallel to the longitudinal axis thereof as the frame is moved along the cable, and a flange on the bushing to prevent movement of the L-shaped rods beyond a predetermined distance toward the cable to limit the penetration of the insulation by the cutting members and thereby protect the cable core.

15. An insulation cutting tool, comprising a frame having an opening therethrough for the insertion of a cable provided with a vulcanized insulating jacket, a plurality of arms pivotally mounted on the frame for movement toward and away from the axis of the opening in the frame, and cutting members carried by the arms for penetrating the jacket on such a cable inserted in the opening in the frame when the arms are drawn toward each other and for slitting the jacket parallel to the axis of the cable when the tool is moved longitudinally with respect to the cable.

16. An insulation cutting tool, comprising a frame having an opening therethrough for the insertion of a cable provided with a vulcanized insulating jacket, a pair of arms each having one of the ends thereof pivotally secured to the frame and designed to be grasped by their free end to cause the arms to swing toward such a cable inserted in the opening in the frame and to move the tool longitudinally along the cable, and a cutting member carried by each of the arms intermediate the ends thereof for penetrating the jacket on the cable when the arms are drawn toward each other and for slitting the jacket .parallel to the axis of the cable when the tool is moved therealong.

17. An insulation cutting tool, comprising a frame having an opening therethrough for the insertion of a cable provided with a vulcanized insulating jacket, a pair of arms each having one of the ends thereof pivotally secured to the frame and designed to be grasped by their free ends to cause the arms to swing toward such a cable inserted in the opening in the frame and to move the tool longitudinally along the cable, a cutting member carried by each of the arms intermediate the ends thereof for penetrating the jacket on the cable when the arms are drawn toward each other and for slitting the jacket parallel to the axis of the cable when the tool is moved therealong, and means for regulating the depth to which the cutting members may penetrate the jacket.

SAMUEL M. MARTIN. 

